It's not o.k to use. The pipe could melt the tank. Aftermarket pipe or stock? Some times you can get a little wiggle room with the pipe by losen all the pipe mounts lighty pull the pipe downward and then re-tighten all pipe mounts. Have you had the pipe off the bike to ensure no other issues? Also theres a rubber pad at the rear under the tank that the tank rests on, make sure it's in place.